ACI Concrete Field Testing Technician

ACI Concrete Field Testing Technician Grade II Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of a slump test?
• Determine air content of concrete
• Measure the compressive strength of concrete
• Determine the consistency or workability of fresh concrete
• Evaluate the water-cement ratio

Rationale: The slump test measures the workability of fresh concrete,

indicating its consistency for placement and finishing.

• When performing a slump test, what is the correct procedure for

filling the cone?

• Fill in one layer without tamping 1 / 4

• Fill in three layers, each tamped 25 times with a rod
• Fill in two layers, tamping 50 times each
• Fill completely, then shake the cone

Rationale: Standard practice involves filling the slump cone in three

layers and tamping each layer 25 times to consolidate the concrete properly.

• The air content of freshly mixed concrete can be measured by which

method?

• Slump test
• Pressure or volumetric method
• Compressive strength test
• Temperature test

Rationale: Air content is determined using either pressure-type or

volumetric air meters for fresh concrete.

• What is the minimum number of specimens required to determine

compressive strength for a single test age?

• 1
• 2
• 3
• 4

Rationale: ACI requires at least three specimens to provide reliable

strength results for a given test age. 2 / 4

• Which type of aggregate is more likely to produce concrete with lower

shrinkage?

• Lightweight aggregate
• Dense, well-graded coarse aggregate
• Rounded gravel
• Recycled aggregate

Rationale: Dense and well-graded aggregates reduce the overall

paste content and shrinkage of concrete.

• Which factor has the greatest effect on the workability of concrete?
• Aggregate shape
• Aggregate gradation
• Water content
• Curing temperature

Rationale: Water content directly affects workability; more water

increases slump and ease of placement.

• When sampling concrete from a truck mixer, the sample should be

taken:

• From the first load discharged
• From several portions discharged during continuous operation
• Only from the center of the drum
• Only from the surface

Rationale: A representative sample requires portions from different

areas during discharge to ensure homogeneity. 3 / 4

• Which tool is required to finish a freshly placed concrete surface?
• Trowel
• Float
• Screed
• All of the above

Rationale: Screeds level, floats smooth, and trowels finish the

surface; all tools are used for proper finishing.

• Which of the following is a common defect caused by rapid drying of

concrete?

• Honeycombing
• Plastic shrinkage cracks
• Segregation
• Bleeding

Rationale: Rapid moisture loss in fresh concrete can cause plastic

shrinkage cracks on the surface.

• During temperature measurement of fresh concrete, the

thermometer should be placed:

• On the surface
• At the center of the mass
• Near the edge of the form
• In a separate water container

Rationale: The center of the mass provides a representative

temperature of the concrete.

• / 4